agid])) { foreach ($g_flag_thread[$flagid] as &$val) { flag_thread_filter($val); } flag_thread_set($flagid, $g_flag_thread[$flagid]); } } return $g_flag_thread[$flagid]; } // 设置缓存 $key = flagid / $val = flagid下tid数组 function flag_thread_set($key, $val) { global $g_flag_thread; FALSE === $g_flag_thread and $g_flag_thread = website_get('flag_thread'); empty($g_flag_thread) and $g_flag_thread = array(); $g_flag_thread[$key] = $val; return website_set('flag_thread', $g_flag_thread); } // 删除flag下tid缓存 function flag_thread_delete_cache($flagid) { global $g_flag_thread; FALSE === $g_flag_thread and $g_flag_thread = website_get('flag_thread'); empty($g_flag_thread) and $g_flag_thread = array(); if (isset($g_flag_thread[$flagid])) { unset($g_flag_thread[$flagid]); website_set('flag_thread', $g_flag_thread); } return TRUE; } // Delete by tid / 通过tid删除flag下的主题和对应flagid缓存 function flag_thread_delete_by_tid($tid) { global $g_flag_thread; FALSE === $g_flag_thread and $g_flag_thread = website_get('flag_thread'); if (empty($g_flag_thread)) { $g_flag_thread = array(); } else { $thread = well_thread_read_cache($tid); $arrlist = flag_thread_find($tid, 1, $thread['flags']); $flagarr = $ids = array(); foreach ($arrlist as $val) { $flagarr[] = $val['flagid']; $ids[] = $val['id']; if (isset($g_flag_thread[$val['flagid']])) unset($g_flag_thread[$val['flagid']]); } website_set('flag_thread', $g_flag_thread); // 主键更新 flag_update($flagarr, array('count-' => 1)); // 主键删除 flag_thread_delete($ids); } return TRUE; } // 主键删除 通过$flagid删除flag下的主题和对应flagid缓存 function flag_thread_delete_by_flagid($flagid) { global $g_flag_thread; FALSE === $g_flag_thread and $g_flag_thread = website_get('flag_thread'); $read = flag_read_cache($flagid); if (empty($read)) return TRUE; $arrlist = flag_thread_find_by_flagid($flagid, 1, $read['count']); if (empty($arrlist)) return TRUE; $flagarr = $ids = array(); $n = 0; foreach ($arrlist as $val) { ++$n; $flagarr[] = $val['flagid']; $ids[] = $val['id']; if (isset($g_flag_thread[$flagid])) unset($g_flag_thread[$flagid]); } website_set('flag_thread', $g_flag_thread); // 主键更新 flag_update($flagarr, array('count-' => $n)); // 主键删除 $r = flag_thread_delete($ids); return $r; } ?>组保留的标签 余下为需要删除的标签 unset($oldtag[$key]); } } } if (!empty($oldtag)) { $tagids = array(); foreach ($oldtag as $tagid => $tagname) { $tagids[] = $tagid; } well_oldtag_delete($tagids, $tid); } $r = well_tag_process($tid, $fid, $create_tag, $tagarr); return $r; } // 删除标签和绑定的主题 function well_oldtag_delete($tagids, $tid) { $pagesize = count($tagids); $arrlist = well_tag_find_by_tagids($tagids, 1, $pagesize); $delete_tagids = array(); // 删除 $tagids = array(); $n = 0; foreach ($arrlist as $val) { ++$n; if (1 == $val['count']) { // 只有一个主题 $delete_tagids[] = $val['tagid']; } else { $tagids[] = $val['tagid']; } } !empty($delete_tagids) and well_tag_delete($delete_tagids); $arlist = well_tag_thread_find_by_tid($tid, 1, $n); if ($arlist) { $ids = array(); foreach ($arlist as $val) $ids[] = $val['id']; well_tag_thread_delete($ids); } !empty($tagids) and well_tag_update($tagids, array('count-' => 1)); } // 标签数据处理 $arr=新提交的数组 $tagarr=保留的旧标签 function well_tag_process($tid, $fid, $new_tags = array(), $tagarr = array()) { if (empty($tid)) return ''; // 新标签处理入库 if ($new_tags) { $threadarr = array(); $tagids = array(); $i = 0; $size = 5; $n = count($tagarr); $n = $n > $size ? $size : $size - $n; foreach ($new_tags as $name) { ++$i; $name = trim($name); $name = stripslashes($name); $name = strip_tags($name); $name = str_replace(array(' ', '#', "@", "$", "%", "^", '&', '·', '<', '>', ';', '`', '~', '!', '¥', '……', ';', '?', '?', '-', '—', '_', '=', '+', '.', '{', '}', '|', ':', ':', '、', '/', '。', '[', ']', '【', '】', '‘', ' ', ' ', ' ', ' ', ' '), '', $name); $name = htmlspecialchars($name, ENT_QUOTES); if ($name && $i <= $n) { // 查询标签 $read = well_tag_read_name($name); if ($read) { // 存在 count+1 $tagids[] = $read['tagid']; } else { // 入库 $arr = array('name' => $name, 'count' => 1); $tagid = well_tag_create($arr); FALSE === $tagid and message(-1, lang('create_failed')); $read = array('tagid' => $tagid, 'name' => $name); } $tag_thread = array('tagid' => $read['tagid'], 'tid' => $tid); $threadarr[] = $tag_thread; $tagarr[$read['tagid']] = $read['name']; } } !empty($threadarr) and tag_thread_big_insert($threadarr); !empty($tagids) and well_tag_update($tagids, array('count+' => 1)); } $json = empty($tagarr) ? '' : xn_json_encode($tagarr); return $json; } ?>内容的栏目 * @param int $category 0列表 1频道 2单页 3外链 * @return array */ function category_list($forumlist, $model = 0, $display = 0, $category = 0) { if (empty($forumlist)) return NULL; static $cache = array(); $key = $model . '-' . $display . '-' . $category; if (isset($cache[$key])) return $cache[$key]; if ($display) { foreach ($forumlist as $k => $val) { if (1 == $val['display'] && 1 == $val['type'] && $val['category'] == $category) { $cache[$key][$k] = $val; } } } else { foreach ($forumlist as $k => $val) { if (1 == $val['type'] && $val['category'] == $category) { $cache[$key][$k] = $val; } } } return empty($cache[$key]) ? NULL : $cache[$key]; } /** * @param $forumlist 所有版块列表 不分模型 * @param int $display 0全部CMS栏目 1在首页和频道显示内容的栏目 * @param int $category 0列表 1频道 2单页 3外链 * @return array */ function category_list_show($forumlist, $display = 0, $category = 0) { if (empty($forumlist)) return NULL; static $cache = array(); $key = $display . '-' . $category; if (isset($cache[$key])) return $cache[$key]; if ($display) { foreach ($forumlist as $k => $val) { if (1 == $val['display'] && 1 == $val['type'] && $val['category'] == $category) { $cache[$key][$k] = $val; } } } else { foreach ($forumlist as $k => $val) { if (1 == $val['type'] && $val['category'] == $category) { $cache[$key][$k] = $val; } } } return empty($cache[$key]) ? NULL : $cache[$key]; } /** * @param $forumlist 所有版块列表 * @return mixed BBS栏目数据(仅列表) 尚未开放bbs频道功能 */ function forum_list($forumlist) { if (empty($forumlist)) return array(); static $cache = array(); if (isset($cache['bbs_forum_list'])) return $cache['bbs_forum_list']; $cache['bbs_forum_list'] = array(); foreach ($forumlist as $_fid => $_forum) { if ($_forum['type']) continue; $cache['bbs_forum_list'][$_fid] = $_forum; } return $cache['bbs_forum_list']; } // 导航显示的版块 function nav_list($forumlist) { if (empty($forumlist)) return NULL; static $cache = array(); if (isset($cache['nav_list'])) return $cache['nav_list']; foreach ($forumlist as $fid => $forum) { if (0 == $forum['nav_display']) { unset($forumlist[$fid]); } } return $cache['nav_list'] = $forumlist; } ?>
2025-06-04 23:01:16 0次
演奏《铃儿响叮当》时,建议使用标准调弦(EADGBE),无需特殊调音或夹变调夹。六根弦从粗到细的音高依次为:6弦E、5弦A、4弦D、3弦G、2弦B、1弦E。这个调弦方式既符合原曲编配需求,也便于初学者上手练习。
标准调弦是吉他最基础的音高标准,其科学依据在于符合西方音乐理论中的四度-三度音程排列。从六弦到一弦的音程关系依次为:六弦E至五弦A为纯四度,五弦A至四弦D为纯四度,四弦D至三弦G为纯四度,三弦G至二弦B为大三度,二弦B至一弦E为纯四度。这种音程组合既保证了和弦按指的便利性,又确保了各弦音高分布的均衡性。
对于调音工具的选择,电子调音器比手机APP更具优势。电子调音器通过琴体振动识别音高,抗干扰能力强;而手机APP在嘈杂环境中容易受环境音影响。调音时需将调音器夹在琴头,拨动琴弦观察显示屏:指针偏左表示音高低,需拧紧弦钮;指针偏右表示音高高,需放松弦钮。特别注意不同弦钮的旋转方向:1-3弦顺时针拧紧升音高,4-6弦逆时针拧紧升音高。
调音过程中需注意力度控制,避免断弦风险。当需要大幅度调整音高(超过两圈)时,应保持脸部远离琴弦区域。标准音高达成时,调音器指针应居中显示绿色标识。建议每天练习前都进行调音校准,长期使用音不准的乐器会导致听觉敏感度下降。
针对《铃儿响叮当》这类圣诞歌曲的演奏,标准调弦完全能满足演奏需求。该曲采用4/4拍节奏型,主要使用C大调音阶构成旋律。指弹版编配时,编曲者会充分考虑标准调弦下的指法便利性,因此无需额外调整音高。初学者可先通过调音器完成基础调音,再结合节拍器以80-100BPM的速度进行分段练习。
保持吉他音准需要定期维护。环境温湿度变化会导致琴颈弯曲度改变,进而影响音高稳定性。建议在每次演奏前检查音准,新琴弦在安装后前48小时需频繁调音。若发现琴弦老化(生锈或张力不足),应及时更换以保证音色质量。标准调弦下的琴弦张力分布均匀,能最大限度延长乐器使用寿命。
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